In the fighting of wildfires, a variety of fire suppression materials are known, as well as equipment for delivery of such fire suppression materials. Perhaps the most common fire suppression material is liquid water. Water can be delivered on a fire, or a space which is to be treated in advance to stop the progression of a fire, in a variety of different ways. For instance, hoses can deliver water from a stationary source such as a fire hydrant, or from a mobile source such as a fire truck. Water tenders are known which can deliver water from tanks on the vehicle to ground adjacent the vehicle, with or without use of hoses.
Aircraft can also be used for delivery of water for fire suppression. While fixed wing aircraft are sometimes used, most often water is delivered by rotating wing aircraft. In a typical such system, a bucket is suspended from a helicopter. The bucket can be dipped into a water reservoir to fill the bucket or be pumped into the bucket. The helicopter then transports the bucket to an area to be treated with the water. A floor or other portion of the bucket is openable to drain the bucket of water and treat the area beneath the bucket. The helicopter then repeats the filling procedure for additional treatment of areas with water. One such line of buckets is provided by S.E.I. Industries, Ltd. of Delta, British Columbia, Canada under the trademark BAMBI BUCKET.
Fire suppression gels are known in the art to have a greater effectiveness in suppressing fire than water alone. Such gels typically begin in the form of a concentrate which can be a solid or a liquid having a high concentration of gel compositions therein. This gel is hydrated to a most desirable water and gel mixture ratio and then is applied to an area to either directly extinguish fire or to treat an area in advance of an approaching fire to impede the progress of the fire, or otherwise suppress fire in the area being treated. Such fire suppression gels, when mixed with water, greatly enhance the effectiveness of the water in suppressing the fire. In particular, the water in the hydrated gel coatings do not evaporate as quickly as water alone, thus maintaining a coating of the area to be treated and discouraging the combustion of combustible materials in the area being treated. One such polymer material is provided under the trademarks FIREWALL ULTRA, provided by BroadRange Wildland Fire Chemicals of Cold Springs, Calif. and FIREWALL II, provided by Eco FireSolutions of Carmichael, Calif., in the form of a liquid emulsion.
While the use of such fire suppression gels is known when treating an area with fire hoses either coupled to stationary sources of water or hydrated gel; or from mobile ground sources (such as tanker trucks), a need exists for an effective airborne fire suppression gel delivery system. While a bucket or other container filled with hydrated gel could be utilized, such an arrangement would be inefficient in that frequent return trips to a source of hydrated gel would be required. Accordingly, a need exists for a system for onboard manufacture of such a water and fire suppression gel mixture on an airborne platform.
Furthermore, water buckets and fixed tanks deliver water to an area to be treated for fire suppression in a rather imprecise manner, merely involving the opening of a lower portion of the bucket or tank. While generally effective for water having a lower fire suppression capacity, with the utilization of fire suppression gel it is desirable that a mixture of water and fire suppression gel be applied to an area to be treated in a precise manner to maximize the fire suppression capability of the gel and minimize the number of repeat trips required and maximize the length of fire line being treated by an airborne vehicle. Thus a need exists for polymer gel emulsion discharge options other than (or augmenting) bucket dumping.
For effective operation of a polymer gel emulsion preparation system a supply of polymer gel emulsion must be carried by the aircraft. A need exists for a convenient location to place such a polymer gel supply tank, which allows such a tank to be readily filled and to position the tank near a center of gravity and center of lift of the aircraft for safe and simple operation of the aircraft and suspended bucket system, and modular and removably attachable so that the aircraft (and bucket) can be reconfigured quickly for various different missions.